I have an old desktop computer that I've been trying to sell for AGES. I guess nobody is looking for computers because it was advertised at a dirt cheap price on craigslist, local papers, etc. Anyways, I was wondering if it would be worth it to set it up as a home file server, a web dev server (I have a web host for actual production use), and maybe host a few server applications (ex: ventrillo). The computer is actually an old Dell that I cannibalized after the motherboard being destroyed by lightning, so it has fairly new parts in it.

The specs are:

P4 3.4GHz w/ HT and Artic Cooling Freezer 7

3GB DDR2 533 RAM

80GB hdd (will upgrade the hard drive if it's even worth using as a
server)

basic dvd rom

430 Watt Thermaltake PSU (it might be important to note that it is only
60% efficiency)

ATI Radeon x600 256MB

Antec 300 case

It's not a really beefy machine, I just can't see giving it away or putting it in the corner to just collect dust. I have Windows Server 2008 R2 Standard and I am confident in my skills in operating most Linux operating systems. I'd also be using it to tinker with when I learn new things in my server admin classes (I'm finishing my 2nd year in college at the moment so I'm still learning)

Also, my house is quite old and the electrical wiring is pretty poor (it MIGHT be up to code, then again, where I live most people don't even know what regulations are or let alone know how to spell it...) Would it be safe to leave it running all day and is it going to run up my electric bill because of the PSU efficiency? I only have 5mbit cable internet, but I won't be running very bandwidth intense services on it so it should be ok.

I should elaborate on why I am concerned about the power. The circuits should be fine, but I'm more concerned about fire hazard. What is the likelihood that the server could cause an electrical fire? Again, thank you all for the feedback!

Well, I have a lower specification machine as a working server (been meaning to upgrade for ages, but, nothing wrong and CPU never goes above 20%).

It may struggle slightly with Windows 2008 - My one can run just fine, but any MMC window seems to take AGES to load, which is a nightmare, as for actual serving - it is fine (e.g. IIS interface is so slow, but actually requesting a site - you wouldn't know it was old hardware!)

After about a week, I downgraded to Windows 2003 and it works very well indeed.

If your house has old wiring, I would look in to buying a UPS. I have five machines here on 24/7 and they always used to blow fuses. After buying the UPSs, they seem to regulate the flow and I haven't had a problem since.

As for the actual power unit - If you are going to leave the machine on 24x7, it really could pay for itself inside a year if you upgrade to a 90%+ certified device. Buy a kill-a-watt type device and measure yourself.

Lastly, as to what to actually run... If you have a need for ASP/ASP.Net or just want a bit of an easier life with regards to off the shelf programs (ok... subjective), use Windows. If however you really want to learn Linux a bit more - use that.

Probably doubtful. A desktop machine doesn't draw much more than a light being left on when it's sitting idle. Here's a page that talks about power usage for a computer.

As for what type of server OS to install, that's really going to be based off what you'd like to use the machine for. If you're comfortable with windows and don't want to relearn anything, install you Server 2008 OS and set the machine up for an application server/file server. Or install Windows Home Server like has been suggested and use it for a interal backup machine. Last, install a version of Linux and use the machine for PHP/MySQL development or your own personal mail server (many options there).

If you are primarily wanting a file server, I'd check into FreeNAS, OpenFiler and Windows Home Server (WHS). Each has distinct advantages, but all should work for you. IMHO WHS and FreeNAS are a bit nicer in terms of disk management. WHS has the advantage of being able to run other windows service based software (such as TVersity). OpenFiler is linux based and can run pretty much anything out there. You could use it as a media hub with a UPnP software, in addition to file serving chores and a network torrent client. FreeNAS is BSD based, and will run a lot of open-source utils as well, but slightly fewer than OpenFiler will.

My suggestion if you plan on running it as a file server (and not using WHS) would be to install your server OS to a thumb drive, on an internally mounted USB adapter. You should be able to run 4 hard drives on your PSU without issue, but wouldn't suggest going with more than that without upgrading the PSU. It should be perfect for file serving, though may be a bit light for UPnP streaming (at least if you need live/on-the-fly re-encoding).